The present invention relates to a novel intraouclar lens having a resiliently movable appendage.
Intraocular lenses have proved to be a superior method of correction of vision after a cataract operation. Although many intraocular lenses have been proposed and developed with a good degree of success, a problem of adjustability remains with intraocular lenses placed in the eye in either the anterior or posterior chamber thereof. This problem is especially acute with fixation of the intraocular lens at the peripheral portion of the eye, namely the angle of the anterior chamber or the ciliary sulcus of the posterior chamber. Reference is made to U.S. Pat. No. 4,159,546 issued to Shearing which discribes an intraocular lens having a pair of springy legs. The Shearing lens is restricted to use after extra capsular cataract surgery and is normally placed in the posterior chamber. The Shearing lens is quite difficult to insert directly into the ciliary sulcus since the surgeon performing the operation is not able to see the springy arms during insertion of the lens.
Each intraocular lens implanted must be properly sized for insertion, which has proved to be a difficult task. Firstly, measurement of the anterior chamber dimensions cannot be accurately determined without surgically entering the eye. Also, the eye changes shape depending on the amount of aqueous humor present therein. Reference is made to U.S. Pat. No. 4,134,161 which proposes a solution to adjusting of the size of an intraocular lens. Also, U.S. patent application Ser. No. 054,953 filed July 5, 1979 represents a step in the evolution of adjustable appendages for intraocular lenses. However, the lens described in the above reference requires a resilient appendage for its workability.
A lens which has adjustable appendages and is capable of using rigid loop material and possesses the ability to provide three point fixation would be highly desirable in the medical field.